‘Unjust sentence’: Pope appears to back Pell

Pope Francis has asked people to pray for those who have "suffered due to an unjust sentence" after Cardinal George Pell's release from prison.

Amid calls for the Vatican to start its own inquiry into Cardinal Pell, the Pope has launched a strong defence of him, although not commenting on him by name.

He tweeted today: "In these days of #Lent, we've been witnessing the persecution that Jesus underwent and how He was judged ferociously, even though He was innocent. Let us #PrayTogether today for all those persons who suffer due to an unjust sentence because of someone had it in for them."

The reference to Jesus comes as the church was set to celebrate Easter behind closed doors, making a parallel between his story and Pell's sentence.

The Pope had said earlier before a mass: "I would like to pray today for all those people who suffer unjust sentences resulting from intransigence (against them).

George Pell leaves HM Prison Barwon in Geelong. Picture: AAP

Pell, 78, spent 404 days behind bars after being found guilty of abusing two choirboys at St Patrick's Cathedral in the 1990s.

He walked free from Barwon Prison today after the High Court ruled the jury's verdicts, on four counts of indecent assault and one of sexual penetration of a child, were unsafe.